The present disclosure relates to a semiconductor manufacturing apparatus used for processing a film formed on a substrate to a desired film thickness and a method of manufacturing a semiconductor device. It also relates to a method of manufacturing an electronic device.
In the course of manufacturing a semiconductor device, there is a step of etching treatment of a film formed on top of a substrate to a predetermined thickness using wet etching. In the step of wet etching, in a case that an initial film thickness of a film subjected to etching treatment (hereinafter, a treated film) varies for each wafer, there has been a problem of occurring variations in final film thicknesses of treated films when etching treatment is carried out in same conditions to all wafers.
With that, in the past, semiconductor manufacturing apparatuses have been practically applied having a function that can suppress variations in film thicknesses of treated films after etching treatment even in a case that initial film thicknesses of the treated films vary. For example, in Japanese Unexamined Patent Application Publication No. 11-251288, as a semiconductor manufacturing apparatus capable of wet etching a treated film formed on top of a substrate to a predetermined film thickness, an apparatus for etching to a desired thickness while carrying out in-situ film measurement is proposed.
Thus, in a semiconductor manufacturing apparatus carrying out in-situ film measurement, that is, wet etching while carrying out film thickness measurement at the time of etching treatment, well controlled etching is enabled because the film thickness measurement is stabled as long as the substrate does not have wiring and the like pattern formed thereon. However, in a case of treating a substrate having a complex pattern, such as a device wafer, due to influence from the pattern during the film thickness measurement, stabled film thickness measurement is difficult to be carried out and the etching controllability turns out to be poor.
As another semiconductor manufacturing apparatus that wet etches a treated film formed on top of a substrate with good controllability, there is a semiconductor manufacturing apparatus carrying out treatment by calculating a treatment time corresponding to a variation in an initial film thickness of a treated film in advance. Thus, in a treatment method by calculating an etching treatment time in advance, a final film thickness of a treated film can be finished uniformly when using a chemical fluid having an invariant etching rate. However, in a case of using a chemical fluid having an etching rate changed over time due to consumption of a chemical fluid component at the time of etching treatment, volatilization and degradation of a chemical fluid component occurring at the time of process standby, and the like, it is difficult to finish a treated film stably in accordance with a preset value.
Accordingly, to terminate wet etching treatment with a film thickness of a treated film after etching in accordance with a preset film thickness even in a wafer having a complex pattern, the treatment time has to be modified for each wafer.
While the above description describes a case of wet etching a treated film, it is also similar in a step of polishing a treated film to a predetermined film thickness using a CMP technique.
In a case of a CMP apparatus, when there is a variation in an initial film thickness of a treated film for each wafer, a polishing treatment time has to be modified for each wafer to terminate the polishing in accordance with a preset film thickness. To calculate a polishing time for each wafer, it is desirable to accurately reflect a rate of polishing on the CMP apparatus. In the past, as shown in Japanese Unexamined Patent Application Publication No. 2004-319574 and Japanese Unexamined Patent Application Publication No. 11-186204, techniques of making an assumption on abrasion of a polishing pad and deterioration of a polishing slurry generated at the time polishing are proposed. However, since there is change over time due to alteration of a polishing pad or volatilization and degradation of a component of a slurry generated during a time of not carrying out polishing treatment, that is, during a process standby time, it is difficult to finish a treated film in accordance with a preset value.